soc/intel/tigerlake: Drop redundant PcieRpEnable

The PcieRpEnable option is redundant to our on/off setting in the
devicetrees. Let's use the common coreboot infrastructure instead.

Thanks to Nicholas for doing all the mainboard legwork!

Change-Id: Iacfef5f032278919f1fcf49e31fa42bcbf1eaf20
Signed-off-by: Nico Huber <nico.h@gmx.de>
Signed-off-by: Nicholas Sudsgaard <devel+coreboot@nsudsgaard.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/79920
Reviewed-by: Sean Rhodes <sean@starlabs.systems>
Reviewed-by: Matt DeVillier <matt.devillier@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/mainboard/google/volteer/variants/baseboard/devicetree.cb b/src/mainboard/google/volteer/variants/baseboard/devicetree.cb
index 078deb2..fe13b77 100644
--- a/src/mainboard/google/volteer/variants/baseboard/devicetree.cb
+++ b/src/mainboard/google/volteer/variants/baseboard/devicetree.cb
@@ -112,28 +112,24 @@
 	# EC memory map range is 0x900-0x9ff
 	register "gen3_dec" = "0x00fc0901"
 
-	# Enable NVMe PCIE 9 using clk 0
-	register "PcieRpEnable[8]" = "1"
+	# NVMe PCIE 9 using clk 0
 	register "PcieRpLtrEnable[8]" = "1"
 	register "PcieClkSrcUsage[0]" = "8"
 	register "PcieClkSrcClkReq[0]" = "0"
 	register "PcieRpSlotImplemented[8]" = "1"
 
-	# Enable Optane PCIE 11 using clk 0
-	register "PcieRpEnable[10]" = "1"
+	# Optane PCIE 11 using clk 0
 	register "PcieRpLtrEnable[10]" = "1"
 	register "HybridStorageMode" = "0"
 	register "PcieRpSlotImplemented[10]" = "1"
 
-	# Enable SD Card PCIE 8 using clk 3
-	register "PcieRpEnable[7]" = "1"
+	# SD Card PCIE 8 using clk 3
 	register "PcieRpLtrEnable[7]" = "1"
 	register "PcieRpHotPlug[7]" = "1"
 	register "PcieClkSrcUsage[3]" = "7"
 	register "PcieClkSrcClkReq[3]" = "3"
 
-	# Enable WLAN PCIE 7 using clk 1
-	register "PcieRpEnable[6]" = "1"
+	# WLAN PCIE 7 using clk 1
 	register "PcieRpLtrEnable[6]" = "1"
 	register "PcieClkSrcUsage[1]" = "6"
 	register "PcieClkSrcClkReq[1]" = "1"
@@ -469,7 +465,6 @@
 		device ref i2c3 on end
 		device ref heci1 on end
 		device ref sata on end
-		device ref pcie_rp1 on end
 		device ref pcie_rp7 on end
 		device ref pcie_rp8 on
 			probe DB_SD SD_GL9755S